// 获取 URL 中指定参数的值
function getParameterByName(name) {
    var url = window.location.href;
    name = name.replace(/[\[\]]/g, '\\$&');

    var regex = new RegExp('[?&]' + name + '(=([^&#]*)|&|#|$)');
    var results = regex.exec(url);

    if (!results) return null;

    if (!results[2]) return '';

    return decodeURIComponent(results[2].replace(/\+/g, ' '));
}
